Many electrical systems involve the use of high voltage electrodes. Examples are gas discharge switches, spark gaps, thyratron switches, and electrostatic precipitators. While the detailed description of the preferred embodiment will be explained in terms of a gas dynamic laser system, those skilled in the art will recognize that the present invention applies equally well to each of the high voltage electrode applications described immediately above.
Gas discharge laser systems produce light by exciting the molecules of a laser gas to an elevated energy state, the excited molecules giving off the light at a characteristic frequency as the excited molecules relax to their original state. The gas molecules are excited by means of an electric field in the gas discharge region. The electric field is created by imposing a high voltage between a pair of electrodes within an enclosure containing the laser gas.
One means of increasing the effectiveness of the discharge region is to infuse it with ions, thereby increasing the number of gas molecules that can be excited when the discharge voltage is applied across the electrodes. One common means of providing such ionization is to flood the discharge region with ionizing particles, such as electrons. The ionizing source is typically an electron gun, source of radioactivity, or source of ultraviolet (UV) radiation. Adding any such system to a discharge system increases the complexity, weight, and cost of the discharge section. Therefore, it is advantageous to provide the discharge section with a self-preionizing electrode.